I have added a partial class to one generated by the Entity Framework. I wanted to add a calculated field that I could bind to my GridView. However, when I try to access the new property, I get an error message that this is a limitation to Entity Framework.Are there any work arounds to accomplish this?
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I'm face of a little problem when using GridView, an EntityDatasource and entity custom properties using a partial class. I'll describe it and I hope that someone has already find the solution because I try to figured out since two days.
View 4 RepliesI have a database table called Animals which I drag on to my Linq to SQL DBML file.
This creates me a class called Animal.
I then create a class to extend it, like so:
public partial class Animal{
//my extra code here
}
But what I also want to do is have a class like this:
public class Zebra : Animal{
//even more extra code here
}
The trouble is I get an InvalidCastException from my repository, when I do this:
Animal a = dataContext.Animals.Where(c=>c.id.Equals(id)).SingleOrDefault();
return (Zebra)a;
I've stripped back my classes to the point where they're completely empty in an attempt to work why it doesn't work. To no avail.
This casting process did used to work in the non-LINQ-2-SQL project that I'm switching to MVC/LINQ.
I am having a meltdown over something that seems so simple and yet isn't working. Here's my scenario.
I have an object structure of tEvents, which contains properties of an event like a run of concerts. tEvents in turn contains an entity set of tEventOptions, which include properties like EventDate, Cancelled etc. I would like to query a list of tEvents using properties of the tEventOptions, for example filtering by date.
My pageis using a calendar object to show event dates. So I am trying to find if any tEvents in the List coming back from the database match the date of the day element being rendered in my Calendar control like so (in this snip 'data' is List and results from a db query):
[code]....
Except r, my query result var, is always true no matter what data it receives. I have tried the sub query using other properties of tEventOption and get the same 'true' result each time. I know that the data does not reflect this result so I clearly have a problem with the structure of my query, but for the life of me I cannot find a way to resolve it.
I have a grid bound to a linqed SP thus:
Session["results"] = db.spGetCaseByNumberOrSurname(txtCaseNum.Text.Trim(), null).ToList();
gvResults.DataSource = Session["results"];
on the sorting of it, i would like to be able to do this..
protected void gvResults_Sorting(object sender, GridViewSortEventArgs e)
{
string sortExpression = e.SortExpression;
List<spGetCaseByNumberOrSurnameResult> data = Session["results"] as List<spGetCaseByNumberOrSurnameResult>;
if (sd == SortDirection.Ascending)
{
sd = SortDirection.Descending;
gvResults.DataSource = data.OrderBy(d => d.GetType().GetProperty(sortExpression));
}
else
{
sd = SortDirection.Ascending;
gvResults.DataSource = data.OrderByDescending(d => d.GetType().GetProperty(sortExpression));
}
gvResults.DataBind();
}
sadly that doesnt do any sorting at all..it in fact errors with "The data source does not support server-side data paging."
i think this maybe an easy one...I have a Gridview, bound to a dataSource with this query:select userid, name, phone from usersI need to change the content of the Name cell to a link, like so:<a href="http://www.domain.com/page.aspx?userid=12345">User's Name</a>
so OnRowDataBound i'm doing this:
e.Row.Cells[1].Text = "<a href="http://www.domain.com/page.aspx?userid=" + e.Row.Cell[0].Text + "">" + e.Row.Cells[1].Text + "</a>";
It all works fine this way. My problem is that i don't want to display the UserId column in the Gridview, but when i attribute it (asp attribute or server-side) Visible="false" to the BoundField UserId, i can't capture it's value to build the Name Cell.
I am following the Nerd Dinner tutorial as I'm learning ASP.NET MVC, and I am currently on Step 3: Building the Model. One part of this section discusses how to integrate validation and business rule logic with the model classes. All this makes perfect sense. However, in the case of this source code, the author only validates one class: Dinner.
What I am wondering is, say I have multiple classes that need validation (Dinner, Guest, etc). It doesn't seem smart to me to repeatedly write these two methods in the partial class:
[code]....
This doesn't "feel" right, but I wanted to check with SO to get opinions of individuals smarter than me on this. I also tested it out, and it seems that the partial keyword on the OnValidate method is causing problems (understandably so). This doesn't seem possible to fix (but I could very well be wrong).
I'm looking to translate an SQL query into linq
INNER JOIN Usrs ON
SAQ.UserId =
Usrs.UserId AND Scan.UserId =
Users.UserId
I'm not sure how to include the "AND" in the LINQ statement.
I have a dgv with a column type = DataGridViewAutoFilterCheckBoxColumn. I want to know if there's a way to I can get that entire column to become disabled (or Enabled = False) so it won't let the user click on the checkboxes.
I tried looking in the "Bound Column Properties" but there isn't an option to disable the entire column.
I first need to apologize in case this has been answered before but I'm a newbie (green as they come) and this error keeps popping up even before I start debugging! There are two errors and the second one is:" Error 2
Missing partial modifier on declaration of type 'WFPKenya2.WFPKenya2'; another partial declaration of this type exists"
Using the following Webservice definition using aClientArgs as a complex type:
[System.Web.Script.Services.ScriptService]
public class Controller : System.Web.Services.WebService {
[WebMethod]
public void save_client(aClientArgs client)
{
// Save client data
}
}
Then defining aClientArgs as a sub-class:
public class aArgs
{
public string id = null;
public string name = null;
}
public class aClientArgs : aArgs
{
public string address = null;
public string website = null;
}
Returns the following WSDL fragment for the save_client args:
<save_client xmlns="http://tempuri.org/">
<client>
<address>string</address>
<website>string</website>
</client>
</save_client>
When I'm expecting the following:
<save_client xmlns="http://tempuri.org/">
<client>
<id>string</id>
<name>string</name>
<address>string</address>
<website>string</website>
</client>
</save_client>
So it appears that the .NET WebService is not treating inherited properties as arguments/variables for purposes of a web service. How do I get .NET to also use the properties of the base class?
For example, let's say I have a HyperLink:
<asp:HyperLink runat="server" Text="Foo" NavigateUrl="foo.aspx" />
How can I set the NavigateUrl on the server side, without having to go the code-behind?
This doesn't work of course:
<asp:HyperLink runat="server" Text="Foo" NavigateUrl="<%= urlString %>" />
(where urlString might be a string I created earlier in the page)And this doesn't work because the HyperLink is not within a data bound control:
<asp:HyperLink runat="server" Text="Foo" NavigateUrl='<%# urlString %>' />
I guess I could just use a standard anchor element:
<a href="<%= urlString %>">Foo</a>
But I'd rather not mix up HTML and ASP.NET controls, and it would be handy to be able to do this for other controls.
here is the code, where i am confused what to write in all the properties and functions of the base class stream?
I want to inherit abstract class Stream, but confused about what to write?
[Code]....
I could'nt understand how to define these Properties,Sub and Functions. How i start?
Is there any way to list all the class in my ASP.Net application(Including class in App_Code and Partial Class(aspx pages and asmx user controls)
View 3 RepliesI have a datakey that I'd like to query from my GridView instead of looping through all the rows and comparing the key of each row. So I was wondering if it was possible to just do a linq query on the gridview (not datatable) and filter with the datakey.
View 4 ReplieseI am using themes to set the Gridview font size and font name. I need to set the boundfield to the same font and size as I want it to be application to all the columns in gridview. How can I specify the boundfield properties in the themes.
View 8 RepliesWhen I populate a gridview with a linq to sql datasource, I get the results I expect, however, when I try to use a linqToSQL query and try to databind that to the gridview, I get no records returns.
My Linq looks fine and I don't recieve any errors, so if someone could take a quick look and point out an obvious flaw.
[Code]....
i have my page who load my gridview as: GRW.datasource=className.List2(2);i have this function in my class
[Code]....
it returns an error , cannot convert single result to queryable!! in " blo= DB.MarketList(TypeID);"
New to Linq and Var type have a method where linq query is executed, want to return the result and assign it to GridView. but method don't take the return type as var.
So was wondering how do i return this query result?
Should i assign this result to DataTable first and make the method return type as DataTable?
Here is the code, This is what i want to do but not sure what is the right way
[Code]....
I am looking for a way to do paging with a GridView when i set the datasource at run time using a linq query. here is my code:
ETDataContext etdc = new ETDataContext();
var accts = from a in etdc.ACCOUNTs
orderby a.account_id
select new
{
Account = a.account_id,
aType = a.SERVICEs.FirstOrDefault().SERVICE_TYPE.service_type_desc,
name = a.SERVICEs.FirstOrDefault().service_name,
[Code]....
But that works well when you use a datatable but not with linq. If I add a rebind in the event, it has to requery 7000 records which can be a little slow. Does anyone know how to fix the paging when using linq like this?
how can I display a linq query in a gridview that has data from multiple tables AND allow the user to edit some of the fields or delete the data from a single table?
I'd like to do this with either a linqdatasource or a linq query. I'm aware I can set the e.Result to the query on the selecting event. I've also been able to build a custom databound control for displaying the linq relations (parent.child).
However, I'm not sure how I can make this work with delete? I'm thinking I may need to handle the delete event with custom code.
I've got a gridview that will allow clients to edit options they've already entered on another page. The gridview has three radio buttons in it each with a value of 1,2,3. The option value in the dataset is 1,2 or 3 respectively. I would like to have the radiobutton with the corresponding value selected in the gridview so they can see what they previously chose and will then be able to edit, if they wish.
Here's my code so far:
[Code]....
i want to validate dropdownlist which is bound to objectdatasource. i am using following code but the listitem <asp:ListItem Value="-1">Select</asp:ListItem> doesnot appear. it shows only items that are stored in database. please help me how can i validate this dropdownlist.
<asp:DropDownList id="drpdwnFID" CausesValidation="true" runat="server" DataSourceID="objDtsrcForums" DataTextField="Title" DataValueField="ForumID" >
<asp:ListItem Value="-1">Select</asp:ListItem>
</asp:DropDownList>
<asp:RequiredFieldValidator ID="rqrValidDropDwn" InitialValue="-1" ErrorMessage="Select Forum" runat="server" ValidationGroup="submit" ControlToValidate="drpdwnFID" Display="None"></asp:RequiredFieldValidator>
I have a gridview that displays the results of a SELECT * from a SqlDataSource. Works great. However one of the fields is a Unique ID linking to another table.
Instead of displaying this Unique ID I would like to do a seperate SQL query like, SELECT name from CONTACTS where UID=UID, and display the name of the item that has the matching Unique ID in the boundField, or another field.
I want to use "if statement" in Linq query. How can I do this situation?
For example:
if txtAge.Text=="", I will not use that in Linq Query.
else txtAge.Text!="", I will use that in Linq Query.
